Spirit-level.



UNITED STATES PATENT OFFICE.

JOSIAH H. VAN LUVAN, 0F WEST PITTSTON, PENNSYLVANIA.

SPIRIT-LEVEL.

SPECIFICATION forming part of Letters Patent No. 662,991, dated December4, 1900.

Application led February 4, 18938, Serial No. 669,167. (No model.)

To all whom, t may concern:

Be itkno'wn that'I, JosrAH ILVAN LUvAN, a citizen of the United States,residing at West Pittston, in the county of Luzerne and State ofPennsylvania, have invented a new and useful Improvement inSpirit-Levels, of which the following is a specification.

My invention relates to certain improvements in spirit-levels, and hasfor one object to provide a device of this character which shall bethoroughly practicable and convenient and adapted to use in all kinds ofconstruction-work where such instruments are required.

Another object of my invention is to provide means for readily andeasily adjusting the said level to determine whether objects are plumbor level and also to determine. the degree of inclination of objects.

A still further object of my invention is to provide improved sightingmeans in connection with the level, which, together with the minuteadjusting means, produces an instrument which can be usedin suchmechanical work as requires the indication of levels, grades, or angles.

With these objects in ,View my invention consists in the novelaraugement and combination of parts, such as will be hereinafter morefully described, and particularly pointed out in the appended claim.

In order to enable others skilled in the art to which my invention mostnearly appertains to make and use the same, I will now proceed todescribe its construction and operation, reference being had to theaccompanying drawings, forming part of this specification, in which-Figure l is a perspective view of a spiritlevel embodying my invention.Fig. 2 is a side elevation of the same. Fig. 3 is a transverse sectionon the line 3 3 of Fig. 2 looking in the direction of the arrow. Fig. 4is a longitudinal section of one end of my device. Fig. 5 is a similarview of the opposite end of my device. Fig. 6 is a detail perspective ofone end of my device, a portion of the end plate being broken away tomore clearly illustrate the shutter for closing and protecting the endsof the sighttube. Fig. 7 is a sectional perspective view of my improvedadjusting mechanism.

In the drawings, A designates the stock or frame of my level, which maybe constructed of wood or any other suitable material and is madesubstantially rectangular in shape. In the longitudinal center of theframe A is formed a semicylindrical recess B for the reception of alevel-tube C, which is filled with the usual liquid used in ordinaryspirit-levels. A slotted plate D is secured over the top of this openingby means of screws or otherwise, having a longitudinal slot providedtherein, so that the level-tube will be easily displayed therethrough.In the sides of the stock A, at a point equidistant from the endsthereof, I provide the socket-pieces E and F, extending transverselythrough the said frame, the socket E carrrying a horizontalleveling-tube E and the socket F carrying a vertical leveling-tube F',the former being used for leveling horizontal surfaces and the latterfor vertical surfaces. Y

Intermediate the socket-pieces E and F and the respective ends of thestock I provide the transverse openings G I-I, in the bottom of which iscarried my improved adjusting means, the construction of which issubstantially the' same in both ends of the said stock, and is shownmore particularly in Figs. 3 and 7 of the drawings, and may be describedas follows: A metallic head I, having anges I' on its upper end, issuitably secured in a mortise extending through the bottom portion ofthe recesses G H and held therein by means of screws. Through the centerof this head I, I provide a screw-threaded opening I2 for the receptionof a screw K. This screw K is provided on its lower end with astationary base K', provided with the shoulders K2, adapted to tit incorrespondingly-shaped recesses provided in the bottom of the head I. Onthe upper end of the screw K, I provide a stationary thumb-nut L, bywhich the screw K may be revolved to adjust or vary the position of thestock A as may be desired. The thumb-nut is large enough to be graspedbetween the thumb and fingers through the recess H and rotatedsufficiently to properly adjust the level. In this manner the entireadjusting mechanism is within the surface of the level, and theadjustment can be made without the use of a screw-driver or otherimplement, and there is no danger of any of the IOO parts being screwedout of the level and lost, as each end of the adj Listing-screw is provided with a permanent head, which prevents its removal.- In the upperpart of the stock or frame A Ais located the sight-tube M, which may beConstructed of either glass or metal, running'longitudinallytherethrough andpositioned slightly to one side of the center of saidframe, so as to leave room for the shutters N, which are provided ateach end of the said tube. On the ends of the frame A, I provide theplates O O', having top and bottom fianges embracing the top and bottomof the said frame and secured thereto by means of screws. Sidey openingsO2 and O3 are provided in these end plates in line with the sighttube M,and the shutters N are pivoted to the said end pieces and adapted toslide in recesses N', provided in the frame in the rear of said endpieces, the purpose of which is to closev the ends of the sight-tubewhen not in use, so as to protect them from dust and dirt. The usualcentering-Wires P are provided in the one end ofthe sight-tube in therear of. its lenses Q, From the above description it will be seen that Ihave provided a device to ascertain if objects are level, plumb, orinclined, also affording means to ascertain the grade of the ground orother surface by sighting at a fixed point which isa known distance fromthe su rface of the ground and Which may be used to streetwork, andgrading for groundwork of i any kind.

While I have illustrated and described the e best meansl now known to mefor carrying out my invention, I do not Wish to be understood asrestricting myself to the exact details of construction shown anddescribed, but hold that any slight changes or variations, such as mightsuggest themselves to the ordinary mechanic, would properly fall Withinthe limit and scope of my invention.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent of the United States, is-

' In a level, the combination with a body having a sight-tube andlevelingetubes, the sighttube being provided with a lens andcentering-wires located near one side of the body, and/the body beingrecessed at each end of the tube toward the opposite side, a plate oneach end of the body, perforated to register With the sight-tube, ashutter pivotally secured to said plate in position to fit in saidrecess and be moved over the end of the sighttube, and means forsupporting the level in a horizontaliposition on an inclined surface.

JOSIAH H. VAN LUVAN. Witnesses:

A. C. HOLDEN, J. J. NICHOLS.

